Keytruda Side Effects
Generic name: pembrolizumab
Medically reviewed by Drugs.com. Last updated on Jul 4, 2021.
Note: This document contains side effect information about pembrolizumab. Some of the dosage forms listed on this page may not apply to the brand name Keytruda.
For the Consumer
Applies to pembrolizumab: intravenous solution
Side effects requiring immediate medical attention
Along with its needed effects, pembrolizumab (the active ingredient contained in Keytruda) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor or nurse immediately if any of the following side effects occur while taking pembrolizumab:
More common
- Black, tarry stools
- bladder pain
- bloating or swelling of the face, arms, hands, lower legs, or feet
- bloody or cloudy urine
- blurred vision
- body aches or pain
- burning, numbness, tingling, or painful sensations
- chills
- clay-colored stools
- confusion
- constipation
- cough
- dark urine
- decreased appetite
- depressed mood
- difficult, burning, or painful urination
- difficulty with breathing
- difficulty with moving
- dizziness
- dry mouth
- dry skin and hair
- ear congestion
- feeling cold
- fever
- flushing
- frequent urge to urinate
- fruit-like breath odor
- hair loss
- headache
- hoarseness or husky voice
- increased hunger
- increased thirst
- increased urination
- itching, skin rash
- joint or bone pain
- loss of voice
- lower back or side pain
- mood or mental changes
- muscle cramps, pain, and stiffness
- nausea
- neck pain
- nervousness
- numbness and tingling around the mouth, fingertips, or feet
- painful or difficult urination
- pale skin
- pounding in the ears
- rapid weight gain
- redness, swelling, or pain of the skin
- runny or stuffy nose
- scaling of the skin on the hands and feet
- slow or fast heartbeat
- sneezing
- sore throat
- sores, ulcers, or white spots on the lips or in the mouth
- stomach cramps, pain or tenderness
- swelling of the face, ankles, or hands
- tingling of the hands or feet
- ulceration of the skin
- unsteadiness or awkwardness
- unusual bleeding or bruising
- unusual tiredness or weakness
- unusual weight gain or loss
- vomiting
- weakness in the arms, hands, legs, or feet
- yellow eyes or skin